The past year has brought some disappointing results from clinical trials testing new Alzheimer’s drugs.
On top of that, a handful of pharmaceutical companies have bowed out of Alzheimer’s drug development altogether.
At the 16th Annual Mild Cognitive Impairment Symposium held recently, reviewed the latest thinking about Alzheimer’s clinical trials and future treatment directions being explored.
What’s still needed, and what pharmaceutical development for Alzheimer’s has lately focused on, are drugs that slow Alzheimer’s progression.
Currently, the big effort is to design randomized controlled trials for drugs that target amyloid, tau, & inflammation “At the right stage of disease for the right patient.”
As we head towards that goal, Gauthier believes we will learn much from the Dominantly Inherited Alzheimer’s Disease Network Trial Unit studies funded by the National Institutes of Health.
Some of the different ways beta-amyloid is being targeted in AD drugs currently being studied.
Up ahead, DIAN-TU investigators plan to test another type of drug, called a β-site amyloid precursor protein cleaving enzyme 1 inhibitor, to block production of excess Aβ peptides in developing AD. The director of the DIAN-TU studies, Randall Bateman, MD, of Washington University in St. Louis, is a noted leader in the field and 2017-20 grantee of BrightFocus’ Alzheimer’s Disease Research program.
These may include drugs that have failed in previous trials.
Drugs already approved to treat other diseases are being evaluated for selective use in Alzheimer’s.
These include angiotensin receptor blockers, angiotensin converting enzyme inhibitors, and insulin-enhancing drugs; biologic agents used in autimmune diseases, such as rheumatoid arthritis; and rho-kinase inhibitors used to treat stroke.
Once a drug is proven effective at delaying the onset of MCI, a condition that can be an early stage of AD), or in delaying or stopping progression to AD, “There will be interest in combining them to achieve larger therapeutic effects,” Gauthier said.
With a drug like aducanumab, which is delivered to the brain by injection, “Would the plan be to set up injection clinics?,” Gauthier wondered aloud.
Since it’s a bioengineered drug that will be costly to manufacture, would it mainly be targeted it to ApoE4 carriers and others at greatest risk? Gauthier also called for clearly defined start and stop rules, including time periods for gauging a drug’s effect, as a way to prepare for optimal use of new drugs.
The knowledge that’s gained will lead to new treatments and also to risk reduction strategies which, if started in middle age or earlier, may help protect younger generations from developing Alzheimer’s.